Circuit interrupting device with reset lockout

ABSTRACT

Resettable circuit interrupting devices, such as GFCI devices, that include reverse wiring protection, and optionally an independent trip portions and/or a reset lockout portion are provided. The reverse wiring protection operates at both the line and load sides of the device so that in the event line side wiring to the device is improperly connected to the load side, fault protection for the device remains. The trip portion operates independently of a circuit interrupting portion used to break the electrical continuity in one or more conductive paths in the device. The reset lockout portion prevents the reestablishing of electrical continuity in open conductive paths if the circuit interrupting portion is non-operational, if an open neutral condition exists or if the device is reverse wired. Methods for ensuring a reset lockout state before shipment are provided.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of application Ser. No. 12/013,577filed Jan. 14, 2008 (allowed Aug. 10, 2009), which was a continuation ofapplication Ser. No. 11/419,689 filed May 22, 2006 (now U.S. Pat. No.7,400,477), which was a continuation of application Ser. No. 09/812,288filed Mar. 20, 2001 (now U.S. Pat. No. 7,049,910), which was acontinuation-in-part of application Ser. No. 09/379,138 filed Aug. 20,1999 (now U.S. Pat. No. 6,246,558), which was a continuation-in-part ofapplication Ser. No. 09/369,759 filed Aug. 6, 1999 (now U.S. Pat. No.6,282,070), which was a continuation-in-part of application Ser. No.09/138,955 filed Aug. 24, 1998 (now U.S. Pat. No. 6,040,967), all ofwhich are incorporated herein in their entirety by reference.

This application is also related to application Ser. No. 09/379,140filed Aug. 20, 1999 (now U.S. Pat. No. 6,288,882), which was acontinuation-in-part of application Ser. No. 09/369,759 filed Aug. 6,1999 (now U.S. Pat. No. 6,282,070), which was a continuation-in-part ofapplication Ser. No. 09/138,955 filed Aug. 24, 1998 (now U.S. Pat. No.6,040,967), all of which are incorporated herein in their entirety byreference.

This application is also related to application Ser. No. 09/204,861filed Dec. 3, 1998 (now U.S. Pat. No. 6,252,407), which was a divisionof application Ser. No. 08/768,689 filed Dec. 18, 1996 (now abandoned),each of which is incorporated herein in its entirety by reference.

This application is also related to commonly owned application Ser. No.09/812,875 filed Mar. 20, 2001 (now U.S. Pat. No. 7,031,125), which wasa continuation-in-part of application Ser. No. 09/688,481 filed Oct. 16,2000, all of which are incorporated herein in their entirety byreference.

BACKGROUND

1. Field

The present application is directed to resettable circuit interruptingdevices including without limitation ground fault circuit interrupters(GFCI's), arc fault circuit interrupters (AFCI's), immersion detectioncircuit interrupters (IDCI's), appliance leakage circuit interrupters(ALCI's), equipment leakage circuit interrupters (ELCI's), circuitbreakers, contactors, latching relays and solenoid mechanisms. Moreparticularly, the present application is directed to circuitinterrupting devices that include a circuit interrupting portion thatcan break electrically conductive paths between a line side and a loadside of the device and between a line side and a user load. Certainembodiments of the present application are directed to circuitinterrupting devices including a reset lockout portion capable ofpreventing the device from resetting if the circuit interrupting portionis not functioning, if an open neutral condition exists or if the deviceis mis-wired. Certain embodiments of the present application aredirected to methods of manufacturing circuit interrupting devices to beinitially in a tripped condition. Certain embodiments of the presentapplication are directed to methods of manufacturing circuitinterrupting devices to be initially in a reset lockout condition.

2. Description of the Related Art

Many electrical wiring devices have a line side, which is connectable toan electrical power supply, and a load side, which is connectable to oneor more loads and at least one conductive path between the line and loadsides. Electrical connections to wires supplying electrical power orwires conducting electricity to the one or more loads are at line sideand load side connections. The electrical wiring device industry haswitnessed an increasing call for circuit breaking devices or systemswhich are designed to interrupt power to various loads, such ashousehold appliances, consumer electrical products and branch circuits.In particular, electrical codes require electrical circuits in homebathrooms and kitchens to be equipped with ground fault circuitinterrupters (GFCI), for example. Presently available GFCI devices, suchas the device described in commonly owned U.S. Pat. No. 4,595,894, usean electrically activated trip mechanism to mechanically break anelectrical connection between the line side and the load side. Suchdevices are resettable after they are tripped by, for example, thedetection of a ground fault. In the device discussed in the '894 patent,the trip mechanism used to cause the mechanical breaking of the circuit(i.e., the conductive path between the line and load sides) includes asolenoid (or trip coil). A test button is used to test the tripmechanism and circuitry used to sense faults, and a reset button is usedto reset the electrical connection between line and load sides.

However, instances may arise where an abnormal condition, caused by forexample a lightning strike, occurs which may result not only in a surgeof electricity at the device and a tripping of the device but also adisabling of the trip mechanism used to cause the mechanical breaking ofthe circuit. This may occur without the knowledge of the user. Undersuch circumstances an unknowing user, faced with a GFCI which hastripped, may press the reset button which, in turn, will cause thedevice with an inoperative trip mechanism to be reset without the groundfault protection available.

Further, an open neutral condition, which is defined in UnderwritersLaboratories (UL) Standard PAG 943A, may exist with the electrical wiressupplying electrical power to such GFCI devices. If an open neutralcondition exists with the neutral wire on the line (versus load) side ofthe GFCI device, an instance may arise where a current path is createdfrom the phase (or hot) wire supplying power to the GFCI device throughthe load side of the device and a person to ground. In the event that anopen neutral condition exists, current GFCI devices, which have tripped,may be reset even though the open neutral condition may remain.

Commonly owned application Ser. No. 09/138,955 filed Aug. 24, 1998 (nowU.S. Pat. No. 6,040,967), which is incorporated herein in its entiretyby reference, describes a family of resettable circuit interruptingdevices capable of locking out the reset portion of the device if thecircuit interrupting portion is non-operational or if an open neutralcondition exists.

Some of the circuit interrupting devices described above have a useraccessible load side connection in addition to the line and load sideconnections. The user accessible load side connection includes one ormore connection points where a user can externally connect to electricalpower supplied from the line side. The load side connection and useraccessible load side connection are typically electrically connectedtogether. An example of such a circuit interrupting device is a GFCIreceptacle, where the line and load side connections are binding screwsand the user accessible load side connection is the plug connection toan internal receptacle. As noted, such devices are connected to externalwiring so that line wires are connected to the line side connection andload side wires are connected to the load side connection. However,instances may occur where the circuit interrupting device is improperlyconnected to the external wires so that the load wires are connected tothe line side connection and the line wires are connected to the loadconnection. This is known as reverse wiring. In the event the circuitinterrupting device is reverse wired, fault protection to the useraccessible load connection may be eliminated, even if fault protectionto the load side connection remains.

Furthermore, studies related to GFCI devices indicate that perhaps10-20% or more of all GFCI devices installed were found to be inoperableby the user. However, after those devices were returned to themanufacturer, most were found to be operational. Accordingly, it hasbeen suggested that the devices were reverse wired by the user(line-load side reversal). Furthermore, regulatory codes and industrystandards codes such as those by Underwriters Laboratories (UL) mayrequire that GFCI devices be manufactured with a warning label advisingthe user to correctly wire the line and load terminals of the device.However, even such warnings may not be adequate as suggested by thestudies above. Furthermore, a reasonably foolproof mis-wiring preventionscheme may obviate the need for such a warning label.

Conventional GFCI devices may utilize a user load such as a facereceptacle. Typically GFCI's are four terminal devices, two phase or ACleads for connection to AC electrical power and two LOAD leads forconnection to downstream devices. If a conventional GFCI is properlywired, the GFCI provides ground fault protection for devices downstreamand the incorporated receptacle. However, if a conventional GFCI isreverse wired, unprotected power is provided to the receptacle face atall times. For example, when a conventional GFCI is reverse wired, theface receptacle is “upstream” from the current imbalance sensor coil.Accordingly, if the conventional GFCI is in either the tripped or normalstate, the face receptacle is provide unprotected power.

In spite of detailed instructions that come packaged with most GFCI'sand identification of AC and LOAD terminals, GFCI's are sometimesmis-wired. One reason that this problem exists is that in newconstruction, both the input line and downstream cables appear identicalwhen the installer is connecting a new ground fault circuit interrupter.This is especially a problem in new construction where there is no poweravailable in order to test which cable is leading current into thedevice.

The problem may be compounded when it is considered that many typicalduplex receptacle GFCI's have a test button that will trip and shut offthe power when pushed to verify operations of internal functions in theGFCI. However, use of the test button does not indicate whether thebuilt in duplex receptacle is protected. Typical users may not be awareof this. Users simply test the device after installation and verify thatthe unit trips upon pressing the test button by way of an audible click,for example. This gives the user a false sense that all is well. What isactually happening when the GFCI is reverse wired is that the GFCIdisconnects power from and protects everything downstream, but does notprotect the receptacle contacts of the GFCI itself. The device will tripdepending on the condition of internal components and irrespective ofhow the GFCI was wired. It does not matter that the GFCI was reversewired when it was tested.

Certain references described devices that attempt to warn the user of areverse wiring condition. For example, one approach utilizes a GFCI withreverse line polarity lamp indicator to indicate proper installation ofthe GFCI. See, for example, U.S. Pat. No. 4,412,193 issued to Bienwaldet al. on Oct. 25, 1983, and assigned to the owner of the presentinvention. However, a push button needs to be manually pressed inaccordance with instructions in order to detect whether the GFCI ismis-wired.

In another example, U.S. Pat. No. 5,477,412 issued to Neiger et al. onDec. 19, 1995, and owned by the assignee of the present invention, isdirected to a ground fault circuit interrupter incorporating mis-wiringprevention circuitry. Mis-wiring sense circuitry automatically triggersthe generation of visual and audible alarms in the event of mis-wiringconditions. The circuit employs an alarm inhibiting technique thatincorporates sense circuitry connected to the AC terminals on one sideof the internal GFCI switches or relays and alarm generation circuitryconnected to the load terminal on the opposite side.

Commonly owned application Ser. No. 09/204,861 filed Dec. 3, 1998, whichis incorporated herein in its entirety by reference, describes a deviceto test for reverse wiring and provide an indication of reverse wiring.

SUMMARY

The present application relates to a resettable circuit interruptingdevices that maintain fault protection for the circuit interruptingdevice even if the device is reverse wired.

In one embodiment, the circuit interrupting device includes a housingand phase and neutral conductive paths disposed at least partiallywithin the housing between line and load sides. Preferably, the phaseconductive path terminates at a first connection capable of beingelectrically connected to a source of electricity, a second connectioncapable of conducting electricity to at least one load and a thirdconnection capable of conducting electricity to at least one useraccessible load. Similarly, the neutral conductive path, preferably,terminates at a first connection capable of being electrically connectedto a source of electricity, a second connection capable of providing aneutral connection to the at least one load and a third connectioncapable of providing a neutral connection to the at least one useraccessible load;

The circuit interrupting device also includes a circuit interruptingportion that is disposed within the housing and configured to causeelectrical discontinuity in one or both of the phase and neutralconductive paths, between said line side and said load side upon theoccurrence of a predetermined condition. A reset portion is disposed atleast partially within the housing and is configured to reestablishelectrical continuity in the open conductive paths.

Preferably, the phase conductive path includes a plurality of contactsthat are capable of opening to cause electrical discontinuity in thephase conductive path and closing to reestablish electrical continuityin the phase conductive path, between said line and load sides. Theneutral conductive path also includes a plurality of contacts that arecapable of opening to cause electrical discontinuity in the neutralconductive path and closing to reestablish electrical continuity in theneutral conductive path, between said line and load sides. In thisconfiguration, the circuit interrupting portion causes the plurality ofcontacts of the phase and neutral conductive paths to open, and thereset portion causes the plurality of contacts of the phase and neutralconductive paths to close.

One embodiment for the circuit interrupting portion uses anelectro-mechanical circuit interrupter to cause electrical discontinuityin the phase and neutral conductive paths, and sensing circuitry tosense the occurrence of the predetermined condition. For example, theelectro-mechanical circuit interrupter includes a coil assembly, amovable plunger attached to the coil assembly and a banger attached tothe plunger. The movable plunger is responsive to energizing of the coilassembly, and movement of the plunger is translated to movement of saidbanger. Movement of the banger causes the electrical discontinuity inthe phase and/or neutral conductive paths.

The circuit interrupting device may also include reset lockout portionthat prevents the reestablishing of electrical continuity in either thephase or neutral conductive path or both conductive paths, unless thecircuit interrupting portion is operating properly. That is, the resetlockout prevents resetting of the device unless the circuit interruptingportion is operating properly. In embodiments where the circuitinterrupting device includes a reset lockout portion, the reset portionmay be configured so that at least one reset contact is electricallyconnected to the sensing circuitry of the circuit interrupting portion,and that depression of a reset button causes at least a portion of thephase conductive path to contact at least one reset contact. Whencontact is made between the phase conductive path and the at least onereset contact, the circuit interrupting portion is activated so that thereset lockout portion is disabled and electrical continuity in the phaseand neutral conductive paths can be reestablished.

The circuit interrupting device may also include a trip portion thatoperates independently of the circuit interrupting portion. The tripportion is disposed at least partially within the housing and isconfigured to cause electrical discontinuity in the phase and/or neutralconductive paths independent of the operation of the circuitinterrupting portion. In one embodiment, the trip portion includes atrip actuator accessible from an exterior of the housing and a trip armpreferably within the housing and extending from the trip actuator. Thetrip arm is preferably configured to facilitate mechanical breaking ofelectrical continuity in the phase and/or neutral conductive paths, ifthe trip actuator is actuated. Preferably, the trip actuator is abutton. However, other known actuators are also contemplated.

In an embodiment, the circuit interrupter is manufactured having abridge circuit separately disconnecting a load side and a user load whenthe circuit interrupter trips. In another embodiment, two single-pole,single throw switching devices are used to switch each power line fromthe load and the user load, respectively. In another embodiment, thecircuit interrupter is manufactured in a reset lockout state. In anotherembodiment, a removable or fixedly connected trip force device isutilized to force a trip upon installation. In another embodiment, anindicator provides an indication of reverse wiring. In anotherembodiment, a separate trip force device is connected to the circuitinterrupter before it is delivered into the stream of commerce. In yetanother embodiment, the circuit interrupter is set to a reset lockoutstate before being delivered into the stream of commerce.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the present application are described hereinwith reference to the drawings, in which similar elements are givensimilar reference characters, wherein:

FIG. 1 is a perspective view of one embodiment of a ground fault circuitinterrupting device according to the present application;

FIG. 2 is side elevational view, partly in section, of a portion of theGFCI device shown in FIG. 1, illustrating the GFCI device in a set orcircuit making position;

FIG. 3 is an exploded view of internal components of the circuitinterrupting device of FIG. 1;

FIG. 4 is a plan view of portions of electrical conductive paths locatedwithin the GFCI device of FIG. 1;

FIG. 5 is a partial sectional view of a portion of a conductive pathshown in FIG. 4;

FIG. 6 is a partial sectional view of a portion of a conductive pathshown in FIG. 4;

FIG. 7 is a side elevational view similar to FIG. 2, illustrating theGFCI device in a circuit breaking or interrupting position;

FIG. 8 is a side elevational view similar to FIG. 2, illustrating thecomponents of the GFCI device during a reset operation;

FIGS. 9-11 are schematic representations of the operation of oneembodiment of the reset portion of the present application, illustratinga latching member used to make an electrical connection between line andload connections and to relate the reset portion of the electricalconnection with the operation of the circuit interrupting portion;

FIG. 12 is a schematic diagram of a circuit for detecting ground faultsand resetting the GFCI device of FIG. 1;

FIG. 13 is a perspective view of an alternative embodiment of a groundfault circuit interrupting device according to the present application;

FIG. 14 is side elevational view, partly in section, of a portion of theGFCI device shown in FIG. 13, illustrating the GFCI device in a set orcircuit making position;

FIG. 15 is a side elevational view similar to FIG. 14, illustrating theGFCI device in a circuit breaking position;

FIG. 16 is a side elevational view similar to FIG. 14, illustrating thecomponents of the GFCI device during a reset operation;

FIG. 17 is an exploded view of internal components of the GFCI device ofFIG. 13;

FIG. 18 is a schematic diagram of a circuit for detecting ground faultsand resetting the GFCI device of FIG. 13;

FIG. 19 is side elevational view, partly in section, of components of aportion of the alternative embodiment of the GFCI device shown in FIG.13, illustrating the device in a set or circuit making position;

FIG. 20 is a side elevational view similar to FIG. 19, illustrating ofthe device in a circuit breaking position;

FIG. 21 is a block diagram of a circuit interrupting system according tothe present application;

FIGS. 22 a-b are partial schematic diagrams of a conventional GFCIproperly wired in FIG. 22 a and reverse wired in FIG. 22 b;

FIGS. 23 a-b are partial schematic diagrams of a GFCI according to anembodiment of the present invention properly wired in FIG. 23 a andreverse wired in FIG. 23 b;

FIGS. 24 a-b are partial schematic diagrams of a GFCI according to ananother embodiment of the present invention having a reset lockout shownproperly wired in FIG. 24 a and reverse wired in FIG. 24 b;

FIG. 25 a is a partial schematic diagram of a GFCI according to ananother embodiment of the present invention utilizing two single polesingle throw switch devices per line;

FIG. 25 b is a partial schematic diagram of a GFCI according to ananother embodiment of the present invention utilizing a dual pole singlethrow switch device with one end shorted per line;

FIG. 26 is a partial schematic diagram of a GFCI according to an anotherembodiment of the present invention utilizing an indicator;

FIG. 27 is a partial schematic diagram of a test connection used toconfigure a GFCI according to an embodiment of the present invention;

FIGS. 28 a-c are flow charts of methods to prepare a circuitinterrupting device according to embodiments of the present invention;and

FIG. 29 is a perspective view of a trip force device according to anembodiment of the present invention.

DETAILED DESCRIPTION OF EMBODIMENTS

The present application contemplates various types of circuitinterrupting devices that are capable of breaking at least oneconductive path at both a line side and a load side of the device. Theconductive path is typically divided between a line side that connectsto supplied electrical power and a load side that connects to one ormore loads. As noted, the various devices in the family of resettablecircuit interrupting devices include: ground fault circuit interrupters(GFCI's), arc fault circuit interrupters (AFCI's), immersion detectioncircuit interrupters (IDCI's), appliance leakage circuit interrupters(ALCI's) and equipment leakage circuit interrupters (ELCI's).

For the purpose of the present application, the structure or mechanismsused in the circuit interrupting devices, shown in the drawings anddescribed hereinbelow, are incorporated into a GFCI receptacle suitablefor installation in a single-gang junction box used in, for example, aresidential electrical wiring system. However, the mechanisms accordingto the present application can be included in any of the various devicesin the family of resettable circuit interrupting devices.

The GFCI receptacles described herein have line and load phase (orpower) connections, line and load neutral connections and useraccessible load phase and neutral connections. The connections permitexternal conductors or appliances to be connected to the device. Theseconnections may be, for example, electrical fastening devices thatsecure or connect external conductors to the circuit interruptingdevice, as well as conduct electricity. Examples of such connectionsinclude binding screws, lugs, terminals and external plug connections.

In one embodiment, the GFCI receptacle has a circuit interruptingportion, a reset portion and a reset lockout. This embodiment is shownin FIGS. 1-11. In another embodiment, the GFCI receptacle is similar tothe embodiment of FIGS. 1-11, except the reset lockout is omitted. Thus,in this embodiment, the GFCI receptacle has a circuit interruptingportion and a reset portion, which is similar to those described inFIGS. 1-12. In another embodiment, the GFCI receptacle has a circuitinterrupting portion, a reset portion, a reset lockout and anindependent trip portion. This embodiment is shown in FIGS. 13-20.

The circuit interrupting and reset portions described herein preferablyuse electro-mechanical components to break (open) and make (close) oneor more conductive paths between the line and load sides of the device.However, electrical components, such as solid state switches andsupporting circuitry, may be used to open and close the conductivepaths.

Generally, the circuit interrupting portion is used to automaticallybreak electrical continuity in one or more conductive paths (i.e., openthe conductive path) between the line and load sides upon the detectionof a fault, which in the embodiments described is a ground fault. Thereset portion is used to close the open conductive paths.

In the embodiments including a reset lockout, the reset portion is usedto disable the reset lockout, in addition to closing the open conductivepaths. In this configuration, the operation of the reset and resetlockout portions is in conjunction with the operation of the circuitinterrupting portion, so that electrical continuity in open conductivepaths cannot be reset if the circuit interrupting portion isnon-operational, if an open neutral condition exists and/or if thedevice is reverse wired.

In the embodiments including an independent trip portion, electricalcontinuity in one or more conductive paths can be broken independentlyof the operation of the circuit interrupting portion. Thus, in the eventthe circuit interrupting portion is not operating properly, the devicecan still be tripped.

The above-described features can be incorporated in any resettablecircuit interrupting device, but for simplicity the descriptions hereinare directed to GFCI receptacles.

Turning now to FIG. 1, the GFCI receptacle 10 has a housing 12consisting of a relatively central body 14 to which a face or coverportion 16 and a rear portion 18 are removably secured. The face portion16 has entry ports 20 and 21 for receiving normal or polarized prongs ofa male plug of the type normally found at the end of a lamp or appliancecord set (not shown), as well as ground-prong-receiving openings 22 toaccommodate a three-wire plug. The receptacle also includes a mountingstrap 24 used to fasten the receptacle to a junction box.

A test button 26 extends through opening 28 in the face portion 16 ofthe housing 12. The test button is used to activate a test operation,that tests the operation of the circuit interrupting portion (or circuitinterrupter) disposed in the device. The circuit interrupting portion,to be described in more detail below, is used to break electricalcontinuity in one or more conductive paths between the line and loadside of the device. A reset button 30 forming a part of the resetportion extends through opening 32 in the face portion 16 of the housing12. The reset button is used to activate a reset operation, whichreestablishes electrical continuity in the open conductive paths.

Electrical connections to existing household electrical wiring are madevia binding screws 34 and 36, where screw 34 is an input (or line) phaseconnection, and screw 36 is an output (or load) phase connection. Itshould be noted that two additional binding screws 38 and 40 (seen inFIG. 3) are located on the opposite side of the receptacle 10. Theseadditional binding screws provide line and load neutral connections,respectively. A more detailed description of a GFCI receptacle isprovided in U.S. Pat. No. 4,595,894, which is incorporated herein in itsentirety by reference. It should also be noted that binding screws 34,36, 38 and 40 are exemplary of the types of wiring terminals that can beused to provide the electrical connections. Examples of other types ofwiring terminals include set screws, pressure clamps, pressure plates,push-in type connections, pigtails and quick-connect tabs.

Referring to FIGS. 2-6, the conductive path between the line phaseconnection 34 and the load phase connection 36 includes contact arm 50which is movable between stressed and unstressed positions, movablecontact 52 mounted to the contact arm 50, contact arm 54 secured to ormonolithically formed into the load phase connection 36 and fixedcontact 56 mounted to the contact arm 54. The user accessible load phaseconnection for this embodiment includes terminal assembly 58 having twobinding terminals 60 which are capable of engaging a prong of a maleplug inserted therebetween. The conductive path between the line phaseconnection 34 and the user accessible load phase connection includes,contact arm 50, movable contact 62 mounted to contact arm 50, contactarm 64 secured to or monolithically formed into terminal assembly 58,and fixed contact 66 mounted to contact arm 64. These conductive pathsare collectively called the phase conductive path.

Similarly, the conductive path between the line neutral connection 38and the load neutral connection 40 includes, contact arm 70 which ismovable between stressed and unstressed positions, movable contact 72mounted to contact arm 70, contact arm 74 secured to or monolithicallyformed into load neutral connection 40, and fixed contact 76 mounted tothe contact arm 74. The user accessible load neutral connection for thisembodiment includes terminal assembly 78 having two binding terminals 80which are capable of engaging a prong of a male plug insertedtherebetween. The conductive path between the line neutral connection 38and the user accessible load neutral connection includes, contact arm70, movable contact 82 mounted to the contact arm 70, contact arm 84secured to or monolithically formed into terminal assembly 78, and fixedcontact 86 mounted to contact arm 84. These conductive paths arecollectively called the neutral conductive path.

Referring to FIG. 2, the circuit interrupting portion has a circuitinterrupter and electronic circuitry capable of sensing faults, e.g.,current imbalances, on the hot and/or neutral conductors. In a preferredembodiment for the GFCI receptacle, the circuit interrupter includes acoil assembly 90, a plunger 92 responsive to the energizing andde-energizing of the coil assembly and a banger 94 connected to theplunger 92. The banger 94 has a pair of banger dogs 96 and 98 whichinteract with a movable latching members 100 used to set and resetelectrical continuity in one or more conductive paths. The coil assembly90 is activated in response to the sensing of a ground fault by, forexample, the sense circuitry shown in FIG. 12. FIG. 12 showsconventional circuitry for detecting ground faults that includes adifferential transformer that senses current imbalances.

The reset portion includes reset button 30, the movable latching members100 connected to the reset button 30, latching fingers 102 and resetcontacts 104 and 106 that temporarily activate the circuit interruptingportion when the reset button is depressed, when in the trippedposition. Preferably, the reset contacts 104 and 106 are normally openmomentary contacts. The latching fingers 102 are used to engage side Rof each contact arm 50, 70 and move the arms 50, 70 back to the stressedposition where contacts 52, 62 touch contacts 56, 66, respectively, andwhere contacts 72, 82 touch contacts 76, 86, respectively.

The movable latching members 102 are, in this embodiment, common to eachportion (i.e., the circuit interrupting, reset and reset lockoutportions) and used to facilitate making, breaking or locking out ofelectrical continuity of one or more of the conductive paths. However,the circuit interrupting devices according to the present applicationalso contemplate embodiments where there is no common mechanism ormember between each portion or between certain portions. Further, thepresent application also contemplates using circuit interrupting devicesthat have circuit interrupting, reset and reset lockout portions tofacilitate making, breaking or locking out of the electrical continuityof one or both of the phase or neutral conductive paths.

In the embodiment shown in FIGS. 2 and 3, the reset lockout portionincludes latching fingers 102 which after the device is tripped, engagesside L of the movable arms 50, 70 so as to block the movable arms 50, 70from moving. By blocking movement of the movable arms 50, 70, contacts52 and 56, contacts 62 and 66, contacts 72 and 76 and contacts 82 and 86are prevented from touching. Alternatively, only one of the movable arms50 or 70 may be blocked so that their respective contacts are preventedfrom touching. Further, in this embodiment, latching fingers 102 act asan active inhibitor that prevents the contacts from touching.Alternatively, the natural bias of movable arms 50 and 70 can be used asa passive inhibitor that prevents the contacts from touching.

Referring now to FIGS. 2 and 7-11, the mechanical components of thecircuit interrupting and reset portions in various stages of operationare shown. For this part of the description, the operation will bedescribed only for the phase conductive path, but the operation issimilar for the neutral conductive path, if it is desired to open andclose both conductive paths. In FIG. 2, the GFCI receptacle is shown ina set position where movable contact arm 50 is in a stressed conditionso that movable contact 52 is in electrical engagement with fixedcontact 56 of contact arm 54. If the sensing circuitry of the GFCIreceptacle senses a ground fault, the coil assembly 90 is energized todraw plunger 92 into the coil assembly 90 so that banger 94 movesupwardly. As the banger moves upwardly, the banger front dog 98 strikesthe latch member 100 causing it to pivot in a counterclockwise directionC (seen in FIG. 7) about the joint created by the top edge 112 and innersurface 114 of finger 110. The movement of the latch member 100 removesthe latching finger 102 from engagement with side R of the remote end116 of the movable contact arm 50, and permits the contact arm 50 toreturn to its pre-stressed condition opening contacts 52 and 56, seen inFIG. 7.

After tripping, the coil assembly 90 is de-energized so that spring 93returns plunger 92 to its original extended position and banger 94 movesto its original position releasing latch member 100. At this time, thelatch member 100 is in a lockout position where latch finger 102inhibits movable contact 52 from engaging fixed contact 56, as seen inFIG. 10. As noted, one or both latching fingers 102 can act as an activeinhibitor that prevents the contacts from touching. Alternatively, thenatural bias of movable arms 50 and 70 can be used as a passiveinhibitor that prevents the contacts from touching.

To reset the GFCI receptacle so that contacts 52 and 56 are closed andcontinuity in the phase conductive path is reestablished, the resetbutton 30 is depressed sufficiently to overcome the bias force of returnspring 120 and move the latch member 100 in the direction of arrow A,seen in FIG. 8. While the reset button 30 is being depressed, latchfinger 102 contacts side L of the movable contact arm 50 and continueddepression of the reset button 30 forces the latch member to overcomethe stress force exerted by the arm 50 causing the reset contact 104 onthe arm 50 to close on reset contact 106. Closing the reset contactsactivates the operation of the circuit interrupter by, for examplesimulating a fault, so that plunger 92 moves the banger 94 upwardlystriking the latch member 100 which pivots the latch finger 102, whilethe latch member 100 continues to move in the direction of arrow A. As aresult, the latch finger 102 is lifted over side L of the remote end 116of the movable contact arm 50 onto side R of the remote end of themovable contact arm, as seen in FIGS. 7 and 11. Contact arm 50 returnsto its unstressed position, opening contacts 52 and 56 and contacts 62and 66, so as to terminate the activation of the circuit interruptingportion, thereby de-energizing the coil assembly 90.

After the circuit interrupter operation is activated, the coil assembly90 is de-energized so that so that plunger 92 returns to its originalextended position, and banger 94 releases the latch member 100 so thatthe latch finger 102 is in a reset position, seen din FIG. 9. Release ofthe reset button causes the latching member 100 and movable contact arm50 to move in the direction of arrow B (seen in FIG. 9) until contact 52electrically engages contact 56, as seen in FIG. 2.

As noted above, if opening and closing of electrical continuity in theneutral conductive path is desired, the above description for the phaseconductive path is also applicable to the neutral conductive path.

In an alternative embodiment, the circuit interrupting devices may alsoinclude a trip portion that operates independently of the circuitinterrupting portion so that in the event the circuit interruptingportion becomes non-operational the device can still be tripped.Preferably, the trip portion is manually activated and uses mechanicalcomponents to break one or more conductive paths. However, the tripportion may use electrical circuitry and/or electro-mechanicalcomponents to break either the phase or neutral conductive path or bothpaths.

For the purposes of the present application, the structure or mechanismsfor this embodiment are also incorporated into a GFCI receptacle, seenin FIGS. 13-20, suitable for installation in a single-gang junction boxin a home. However, the mechanisms according to the present applicationcan be included in any of the various devices in the family ofresettable circuit interrupting devices.

Turning now to FIG. 13, the GFCI receptacle 200 according to thisembodiment is similar to the GFCI receptacle described in FIGS. 1-12.Similar to FIG. 1, the GFCI receptacle 200 has a housing 12 consistingof a relatively central body 14 to which a face or cover portion 16 anda rear portion 18 are, preferably, removably secured.

A trip actuator 202, preferably a button, which is part of the tripportion to be described in more detail below, extends through opening 28in the face portion 16 of the housing 12. The trip actuator is used, inthis exemplary embodiment, to mechanically trip the GFCI receptacle,i.e., break electrical continuity in one or more of the conductivepaths, independent of the operation of the circuit interrupting portion.

A reset actuator 30, preferably a button, which is part of the resetportion, extends through opening 32 in the face portion 16 of thehousing 12. The reset button is used to activate the reset operation,which re-establishes electrical continuity in the open conductive paths,i.e., resets the device, if the circuit interrupting portion isoperational.

As in the above embodiment, electrical connections to existing householdelectrical wiring are made via binding screws 34 and 36, where screw 34is an input (or line) phase connection, and screw 36 is an output (orload) phase connection. It should be noted that two additional bindingscrews 38 and 40 (seen in FIG. 3) are located on the opposite side ofthe receptacle 200. These additional binding screws provide line andload neutral connections, respectively. A more detailed description of aGFCI receptacle is provided in U.S. Pat. No. 4,595,894, which isincorporated herein in its entirety by reference.

Referring to FIGS. 4-6, 14 and 17, the conductive paths in thisembodiment are substantially the same as those described above. Theconductive path between the line phase connection 34 and the load phaseconnection 36 includes, contact arm 50 which is movable between stressedand unstressed positions, movable contact 52 mounted to the contact arm50, contact arm 54 secured to or monolithically formed into the loadphase connection 36 and fixed contact 56 mounted to the contact arm 54(seen in FIGS. 4, 5 and 17). The user accessible load phase connectionfor this embodiment includes terminal assembly 58 having two bindingterminals 60 which are capable of engaging a prong of a male pluginserted therebetween. The conductive path between the line phaseconnection 34 and the user accessible load phase connection includes,contact arm 50, movable contact 62 mounted to contact arm 50, contactarm 64 secured to or monolithically formed into terminal assembly 58,and fixed contact 66 mounted to contact arm 64. These conductive pathsare collectively called the phase conductive path.

Similarly, the conductive path between the line neutral connection 38and the load neutral connection 40 includes, contact arm 70 which ismovable between stressed and unstressed positions, movable contact 72mounted to contact arm 70, contact arm 74 secured to or monolithicallyformed into load neutral connection 40, and fixed contact 76 mounted tothe contact arm 74 (seen in FIGS. 4, 6 and 17). The user accessible loadneutral connection for this embodiment includes terminal assembly 78having two binding terminals 80 which are capable of engaging a prong ofa male plug inserted therebetween. The conductive path between the lineneutral connection 38 and the user accessible load neutral connectionincludes, contact arm 70, movable contact 82 mounted to the contact arm70, contact arm 84 secured to or monolithically formed into terminalassembly 78, and fixed contact 86 mounted to contact arm 84. Theseconductive paths are collectively called the neutral conductive path.

There is also shown in FIG. 14, mechanical components used duringcircuit interrupting and reset operations according to this embodimentof the present application. Although these components shown in thedrawings are electro-mechanical in nature, the present application alsocontemplates using semiconductor type circuit interrupting and resetcomponents, as well as other mechanisms capable of making and breakingelectrical continuity.

The circuit interrupting device according to this embodimentincorporates an independent trip portion into the circuit interruptingdevice of FIGS. 1-12. Therefore, a description of the circuitinterrupting, reset and reset lockout portions are omitted.

Referring to FIGS. 14-16, an exemplary embodiment of the trip portionaccording to the present application includes a trip actuator 202,preferably a button, that is movable between a set position, wherecontacts 52 and 56 are permitted to close or make contact, as seen inFIG. 14, and a trip position where contacts 52 and 56 are caused toopen, as seen in FIG. 15. Spring 204 normally biases trip actuator 202toward the set position. The trip portion also includes a trip arm 206that extends from the trip actuator 202 so that a surface 208 of thetrip arm 206 moves into contact with the movable latching member 100,when the trip button is moved toward the trip position. When the tripactuator 202 is in the set position, surface 208 of trip arm 202 can bein contact with or close proximity to the movable latching member 100,as seen in FIG. 14. Of course the trip button may be labeled as astandard test button.

In operation, upon depression of the trip actuator 202, the tripactuator pivots about point T of pivot arm 210 (seen in FIG. 15)extending from strap 24 so that the surface 208 of the trip arm 206 cancontact the movable latching member 100. As the trip actuator 202 ismoved toward the trip position, trip arm 206 also enters the path ofmovement of the finger 110 associated with reset button 30 thus blockingthe finger 102 from further movement in the direction of arrow A (seenin FIG. 15). By blocking the movement of the finger 110, the trip arm206 inhibits the activation of the reset operation and, thus, inhibitssimultaneous activation of the trip and reset operations. Furtherdepression of the trip actuator 202 causes the movable latching member100 to pivot about point T in the direction of arrow C (seen in FIG.15). Pivotal movement of the latching member 100 causes latching finger102 of latching arm 100 to move out of contact with the movable contactarm 50 so that the arm 50 returns to its unstressed condition, and theconductive path is broken. Resetting of the device is achieved asdescribed above. An exemplary embodiment of the circuitry used to sensefaults and reset the conductive paths is shown in FIG. 18.

As noted above, if opening and closing of electrical continuity in theneutral conductive path is desired, the above description for the phaseconductive path is also applicable to the neutral conductive path.

An alternative embodiment of the trip portion will be described withreference to FIGS. 19 and 20. In this embodiment, the trip portionincludes a trip actuator 202 that at is movable between a set position,where contacts 52 and 56 are permitted to close or make contact, as seenin FIG. 19, and a trip position where contacts 52 and 56 are caused toopen, as seen in FIG. 20. Spring 220 normally biases trip actuator 202toward the set position. The trip portion also includes a trip arm 224that extends from the trip actuator 202 so that a distal end 226 of thetrip arm is in movable contact with the movable latching member 100. Asnoted above, the movable latching member 100 is, in this embodiment,common to the trip, circuit interrupting, reset and reset lockoutportions and is used to make, break or lockout the electricalconnections in the phase and/or neutral conductive paths.

In this embodiment, the movable latching member 100 includes a rampedportion 100 a which facilitates opening and closing of electricalcontacts 52 and 56 when the trip actuator 202 is moved between the setand trip positions, respectively. To illustrate, when the trip actuator202 is in the set position, distal end 226 of trip arm 224 contacts theupper side of the ramped portion 100 a, seen in FIG. 19. When the tripactuator 202 is depressed, the distal end 226 of the trip arm 224 movesalong the ramp and pivots the latching member 60 about point P in thedirection of arrow C causing latching finger 102 of the latching member100 to move out of contact with the movable contact arm 50 so that thearm 50 returns to its unstressed condition, and the conductive path isbroken. Resetting of the device is achieved as described above.

The circuit interrupting device according to the present application canbe used in electrical systems, shown in the exemplary block diagram ofFIG. 21. The system 240 includes a source of power 242, such as AC powerin a home, at least one circuit interrupting device, e.g., circuitinterrupting device 10 or 200, electrically connected to the powersource, and one or more loads 244 connected to the circuit interruptingdevice. As an example of one such system, AC power supplied to singlegang junction box in a home may be connected to a GFCI receptacle havingone of the above described reverse wiring fault protection, independenttrip or reset lockout features, or any combination of these features maybe combined into the circuit interrupting device. Household appliancesthat are then plugged into the receptacle become the load or loads ofthe system.

A circuit interrupting device having a reset lockout device and aseparate user load break point may be desirable.

Referring to FIGS. 22 a-b, a prior art circuit interrupting device, GFCI300 is shown. Predetermined condition sensor 310 will open switchdevices 312, 314 in order to isolate the line Phase 302 and Neutral 306from the Load, 304 and 308, respectively. As can be appreciated, whenthe device is reverse wired as shown in FIG. 22 b, the user load,receptacle 320 is not protected by the sensor 310.

Referring to FIGS. 23 a-b, portions of a circuit interrupting deviceaccording to another embodiment of the present invention is shown (GFCI400). The device is properly wired in FIG. 23 a and reverse wired inFIG. 23 b. Predetermined condition sensor 410 will open switch devices412, 414 in order to isolate the line Phase 402 and Neutral 406 from theLoad, 404 and 408, respectively. As can be appreciated, when the deviceis reverse wired as shown in FIG. 23 b, the user load, receptacle 420 isprotected by the sensor 410 when the switch devices are tripped. As canbe appreciated, if the device does not include a reset lockout, it maybe reset, even though it is reverse wired. As also shown in FIG. 5, atwo contact switch 414 may be utilized to separately break the lineconnection 402, 406 from the load side 404, 408 and a user load 420.Such a configuration can be considered to be a bridge circuit, as shownin FIG. 24 a, the configuration may include conductors crossing over ina bridge configuration.

As shown in FIGS. 1-12 and the corresponding detailed description above,a mechanical reset lockout device is provided.

As can be appreciated, multiple failure modes are anticipated forcircuit interrupters and they may also be designed to protect againstvarious faults. For instance, GFCI's generally protect against groundcurrent imbalances. They generally protect against grounded neutrals byusing two sensing transformers in order to trip the device when agrounded neutral fault occurs. As can be appreciated, a GFCI may protectagainst open neutrals. Such protection may be provided in corded GFCI'sbecause the wires are flexed, whereas the receptacle GFCI is a fixedinstallation. Accordingly, as can be appreciated, an open neutral can beprotected against by utilizing a constant duty relay solenoid switchpowered across the phase and neutral of the line, for example, across 38and 34 of FIG. 18. In such an instance, if power went out by the neutralopening, the constant duty coil would fire and open the phase andneutral line conductors.

The GFCI of an embodiment of the present invention also protects againstreverse wiring.

Referring to FIGS. 24 a-b, portions of a circuit interrupting deviceaccording to another embodiment of the present invention is shown (GFCI401). The device is properly wired in FIG. 24 a and reverse wired inFIG. 24 b. Predetermined condition sensor 410 will open switch devices412, 414 in order to isolate the line Phase 402 and Neutral 406 from theLoad, 404 and 408, respectively. As can be appreciated, when the deviceis reverse wired as shown in FIG. 24 b, the user load, receptacle 420 isprotected by the sensor 410 when the switch devices are tripped. As canbe appreciated, if the device does include a reset lockout, it may notbe reset, even though it is reverse wired. The reset lockout will testthe device be moving contact 414 to 422 along A-B such that a circuitthrough current limiting resistor 424 is established and picked up bysensor 410, preferably a toroid coil. Because a two contact switch 414is utilized to separately break the line connection 402, 406 from theload side 404, 408 and a user load 420, when reverse wired as in FIG. 24b, the reset lockout test across resistor 424 will not work because thepower from the line is isolated by switch 414.

Referring to FIGS. 25 a-b, circuit interrupting devices 403, 405according to other embodiments of the invention may utilize a bridgecircuit in varying configurations. For example, device 403 preferablyutilizes two single-pole, single throw mechanical switches 430, 432 toisolate a line. Other switch devices including semiconductor switchesmay be used. Furthermore, device 405 utilizes a ganged double-pole,single throw switch with one end tied together 444.

Referring to FIG. 26, a circuit interrupting device 407 according toanother embodiment of the present invention preferably includes anindicator for providing an indication of a reverse wiring condition. Ascan be appreciated, the device 407 with a circuit bridge and resetlockout may have a user load 420 protected and open from the source ofpower. The user load may be a receptacle 420. However, it may bedesirable to provide an indication of a reverse wiring condition even ifthe device is tripped and “safe.” Such an indication may relieve userfrustration in ascertaining a problem. Accordingly, this embodimentutilizes switches 452 and 454 that operate to connect indicator 450 tothe side of the circuit interrupter that normally has the load (404 and408). Switches 452 and 454 are preferably mechanical switches gangedwith switches 412 and 414, respectively. However, other switch devicessuch as semiconductor switches may be used. If device 407 is reversewired as shown and the device is tripped, switches 452 and 454 willsignal indicator 450 to activate. The switches preferably switch powerto the indicator that preferably includes a neon lamp. However, otherindicators such as audio, visual or communication indicators may beused. Similarly, the indicator 450 may be powered from a source otherthan the source of power to the circuit interrupting device and may bebattery powered and may receive only an activate signal from switches452 and 454.

In embodiments of the present invention utilizing a mechanical lockoutmechanism, the device may be manufactured such that the circuitinterrupter is provided to a user in a reset lockout state.

Referring to FIG. 28 a, a method of preparing a circuit interruptingdevice is provided 500. As shown, a circuit interrupting device may bemanufactured 510 such that the circuit interrupting device ismanufactured in a reset lockout state 520. The device manufacture iscompleted 522. Optionally, the reset button is tested when the device isnot powered to ensure that reset is not possible 524. Thereafter thedevice 400 may be placed in the stream of commerce 526.

Referring to FIG. 28 b, a method of preparing a circuit interruptingdevice is provided 500. As shown, a circuit interrupting device may bemanufactured 510 such that the circuit interrupting device ismanufactured in a reset lockout state 520. The device manufacture iscompleted 522. Optionally, the reset button is tested when the device isnot powered to ensure that reset is not possible 524. Thereafter thedevice 400 may be placed in the stream of commerce 526.

Referring to FIGS. 27 and 28 c, a method of preparing a circuitinterrupting device is provided. A lockout set apparatus such as a testmock up in order to achieve a lockout state may be used before thecircuit interrupting device is delivered into the stream of commerce.For example, a GFCI circuit interrupter that has a test mechanism, areset lockout mechanism and a bridge reverse wiring user load protectionmechanism as described above may be manufactured and connected to apower source. The test mechanism may be initiated in order to set thereset lockout mechanism to the lockout state. The GFCI circuitinterrupter is then delivered into the stream of commerce in the resetlockout state. As can be appreciated, quality assurance steps may beperformed and the manufacture in a tripped state may be part of aquality assurance task. As shown, a circuit interrupting device such asGFCI 400 may be connected to a test power supply 490 in order to presetthe device into a reset lockout state before shipping it to users. Amethod of ensuring the device is shipped in the reset lockout state isdescribed 540. During manufacture 541 of the device 400, a test buttonis provided 542. After manufacture, a power source 490 is connected tothe device 544. The trip test is activated to trip the device, therebysetting a reset lockout state 546. Thereafter the device 400 may beplaced in the stream of commerce 548. For example, a quality assurancetask may be done with or about 544.

Referring to FIGS. 1 and 29, a trip force device 610 is provided. Asshown, the device has a body 638 capable of exerting force on a tripforce protrusion 640 when the trip force device is inserted into areceptacle of a circuit interrupting device 10. As can be appreciated,prongs 631, 632, 633 and 634 may be inserted into a circuit interruptingdevice 10 such that protrusion 640 will depress test button 26.Accordingly, the device 10 will be set to trip when installed. Thedevice 10 may be fitted with such a trip force device 610 before it isplaced into the stream of commerce.

An embodiment that may be described with reference to FIG. 1 is acircuit interrupting device having a face or cover portion 16 and a testbutton 26. A removable test force tab (not shown) may be attached ormolded into cover 16. When a user installed the circuit interruptingdevice 10, the device would be tripped and a reset lockout state therebynecessarily set. Thereafter, the removable test force tab may be removedand the device will only reset if the circuit interrupter isoperational, an open neutral condition does not exist and the device isnot reverse wired.

As can be appreciated, if a reset lockout device utilizes electronicmeans such as non-volatile memory to store a state condition variable,such device may be manufactured in the reset lockout state orinitialized to such a state before delivery.

As noted, although the components used during circuit interrupting anddevice reset operations are electro-mechanical in nature, the presentapplication also contemplates using electrical components, such as solidstate switches and supporting circuitry, as well as other types ofcomponents capable or making and breaking electrical continuity in theconductive path.

While there have been shown and described and pointed out thefundamental features of the invention, it will be understood thatvarious omissions and substitutions and changes of the form and detailsof the device described and illustrated and in its operation may be madeby those skilled in the art, without departing from the spirit of theinvention.

1. A resettable circuit interrupting device comprising: an inputelectrical hot-line connection terminal; an input electricalneutral-line connection terminal; an output electrical hot-lineconnection terminal; an output electrical neutral-line connectionterminal; a resettable circuit interrupter providing at least one of:(a) a first interruptible connection along a first electricallyconductive path between said input and output hot-line connectionterminals, and (b) a second interruptible connection along a secondelectrically conductive path between said input and output neutral-lineconnection terminals; said resettable circuit interrupter having: (i) afirst state in which at least one of said interruptible connectionspresents a closed electrical circuit condition along its electricallyconductive path, (ii) a second state in which said at least oneinterruptible connection presents an open electrical circuit conditionalong its electrically conductive path, (iii) an electrically operablecircuit which causes transition from said first state to said secondstate when triggered, and (iv) a manually operable mechanism forresetting from said second state to said first state only ifpredetermined conditions are satisfied; a fault-sensing circuitconfigured and connected to monitor currents flowing along said firstand second conductive paths and to automatically trigger said circuitinterrupter from said first state to said second state if unequalcurrents are detected flowing along said first and second conductivepaths; and a control circuit connected to said resettable circuitinterrupter and to said fault-sensing circuit, said control circuitbeing engaged by said manually operable mechanism and configured toprevent resetting of the interrupter from said second state to saidfirst state unless said predetermined conditions are satisfied, saidpredetermined conditions including at least: (a) the fault-sensingcircuit remains operative, and (b) the electrically operable circuitremains operative.
 2. A resettable circuit interrupting device as inclaim 1, wherein said first and second interruptible connections aredisposed within a semi-conductor switching device.
 3. A resettablecircuit interrupting device as in claim 1, wherein said at least oneinterruptible connection comprises electro-mechanically and/or manuallyoperated switch contacts that can be moved together and apart.
 4. Aresettable circuit interrupting device as in claim 3, wherein saidmanually operable mechanism comprises a manually operated spring-loadedreset switch configured when pushed against spring-loading to establishsaid control circuit causing a forced instance of unequal current flowsin said first and second conductive paths by pushing in a firstdirection against a latch finger which is engaged with a movableelectrical contact, said latch finger being thereafter shifted tore-engage said movable contact in a second opposite direction and tomove the contact towards a reset condition where said first and secondinterruptible connections are in closed electrical circuit conditionsonly if said forced instance of unequal current flows is sensed by thefault-sensing circuit.
 5. A resettable circuit interrupting device as inclaim 4, wherein said forced instance of unequal current flows sensed bythe fault-sensing circuit also causes an operation by said electricallyoperated circuit to insure its continued working condition.
 6. Aresettable circuit interrupting device comprising: an input electricalhot-line connection terminal; an input electrical neutral-lineconnection terminal; an output electrical hot-line connection terminal;an output electrical neutral-line connection terminal; a resettablecircuit interrupter providing at least one of: (a) a first interruptibleconnection along a first electrically conductive path between said inputand output hot-line connection terminals and (b) a second interruptibleconnection along a second electrically conductive path between saidinput and output neutral-line connection terminals; a fault-sensingcircuit configured and connected (a) to detect an abnormal currentcondition of current flowing along said first and/or second conductivepaths and (b) to change said at least one of the first and secondinterruptible connections from closed to open electrical circuitconditions if abnormal current condition is detected; and areset-lockout circuit connected to said resettable circuit interrupterand to said fault-sensing circuit, said reset-lockout circuit beingconfigured to prevent resetting of said at least one of the first andsecond interruptible connections from open to closed electrical circuitconditions unless said fault-sensing circuit is successfully tested andfound operable to detect said abnormal current condition during anattempted resetting operation.
 7. A resettable circuit interruptingdevice as in claim 6, wherein said first and second interruptibleconnections are disposed within a semi-conductor switching device.
 8. Aresettable circuit interrupting device as in claim 6, wherein said firstand second interruptible connections comprise electro-mechanicallyand/or manually operated switch contacts that can be moved together andapart.
 9. A resettable circuit interrupting device as in claim 8,comprising a manually operated spring-loaded reset switch configuredwhen pushed against spring-loading to establish a test circuit causing aforced instance of said abnormal current condition by pushing in a firstdirection against a latch finger which is engaged with a movableelectrical contact, said latch finger being thereafter shifted tore-engage said movable contact in a second opposite direction and tomove the contact towards a reset condition where said first and secondinterruptible connections are in closed electrical circuit conditionsonly if said forced instance of abnormal current condition is sensed bythe fault-sensing circuit.
 10. A resettable circuit interrupting deviceas in claim 6, wherein said fault-sensing circuit detects unequalcurrents flowing along said first and second conductive paths as saidabnormal current condition.
 11. A method for insuring continued safeoperation of a resettable circuit interrupting device having an inputelectrical hot-line connection terminal, an input electricalneutral-line connection terminal, an output electrical hot-lineconnection terminal, an output electrical neutral-line connectionterminal, a first interruptible connection along a first electricallyconductive path between said input and output hot-line connectionterminals and a second interruptible connection along a secondelectrically conductive path between said input and output neutral-lineconnection terminals, said circuit interrupting device having: (i) afirst state in which said interruptible connections present a closedelectrical circuit condition along each of said first and secondelectrically conductive paths, (ii) a second state in which saidinterruptible connections present an open electrical circuit conditionalong each of said first and second electrically conductive paths, (iii)an electrically operable circuit which causes transition from said firststate to said second state when triggered, and (iv) a manually operablemechanism for resetting from said second state to said first state, saidmethod comprising: monitoring currents flowing along said first andsecond conductive paths and automatically triggering said circuitinterrupting device from said first state to said second state ifunequal currents are detected flowing along said first and secondconductive paths; and when said manually operable mechanism is used,preventing resetting from said second state to said first state unlesssaid predetermined conditions are satisfied, said predeterminedconditions including at least: (a) the fault-sensing circuit remainsoperative, and (b) the electrically operable circuit remains operative.12. A method as in claim 11, wherein said preventing step furthercomprises: moving a latch from a first position to a second position,where the second position blocks said interruptible connection movingfrom said second state to said first state.
 13. A method as in claim 11,wherein said first and second interruptible connections compriseelectro-mechanically and/or manually operated switch contacts that canbe moved together and apart.
 14. A method as in claim 13, furthercomprising: actuating said manually operable mechanism; triggering atest circuit causing a forced instance of unequal current flows in saidfirst and second conductive paths by pushing in a first directionagainst a latch finger which is engaged with a movable electricalcontact; moving said latch finger to re-engage said movable contact in asecond opposite direction and to move the contact towards a resetcondition where said first and second interruptible connections are inclosed electrical circuit conditions only if said forced instance ofunequal current flows is sensed by the fault-sensing circuit.
 15. Amethod as in claim 14, wherein said forced instance of unequal currentflows sensed by the fault-sensing circuit also causes an operation bysaid electrically operated circuit to insure its continued workingcondition.
 16. A method for insuring continued safe operation of aresettable circuit interrupting device having an input electricalhot-line connection terminal, an input electrical neutral-lineconnection terminal, an output electrical hot-line connection terminal,an output electrical neutral-line connection terminal, a firstinterruptible connection along a first electrically conductive pathbetween said input and output hot-line connection terminals and a secondinterruptible connection along a second electrically conductive pathbetween said input and output neutral-line connection terminals, saidmethod comprising: detecting an abnormal current condition of currentflowing along said first and/or second conductive paths andautomatically changing said first and second interruptible connectionsfrom closed to open electrical circuit conditions if abnormal currentcondition is detected; and preventing resetting of said first and secondinterruptible connections from open to closed electrical circuitconditions unless said resettable circuit interrupting device issuccessfully tested and found operable.
 17. A method as in claim 16,wherein said first and second interruptible connections are disposedwithin a semi-conductor switching device.
 18. A method as in claim 16,wherein said first and second interruptible connections compriseelectro-mechanically and/or manually operated switch contacts that canbe moved together and apart.
 19. A method as in claim 18, furthercomprising: actuating a manually operated spring-loaded reset switch topush against spring-loading to establish a test circuit causing a forcedinstance of said abnormal current condition by pushing in a firstdirection against a latch finger which is engaged with a movableelectrical contact, said latch finger being thereafter shifted byoperation of the fault-sensing circuit to re-engage said movable contactin a second opposite direction thereby causing the spring-loading tomove the contact towards a reset condition where said first and secondinterruptible connections are in closed electrical circuit conditionsonly if said forced instance of abnormal current condition is sensed bythe fault-sensing circuit.
 20. A method as in claim 16, wherein saidfault-sensing circuit detects unequal currents flowing along said firstand second conductive paths as said abnormal current condition.
 21. Aresettable circuit interrupting device as in claim 3, wherein said atleast one of first and second interruptible connections comprises alatch member that is movable between a first and a second position withrespect to a respectively corresponding movable electrically conductivepath, each of said first and second latch positions inhibiting anychanges in said at least one of first and second interruptibleconnections between said first and second states.
 22. A resettablecircuit interrupting device comprising: a pair of fixed contact strips,each of the fixed contact strips having a fixed contact; a pair ofmovable contact strips, each of the movable contact strips having afixed end and a movable end, each of the movable ends having a movablecontact arranged for contacting one of the fixed contacts; a resetcomponent comprising a reset button configured to engage a movableassembly including a latch capable of inhibiting at least one of themovable contact strips from moving from a first state to a second stateand from a second state to a first state; and a trip componentconfigured to release the at least one movable contact strip from one ofsaid first and second states upon detecting a predetermined condition.23. A reseftable circuit interrupting device as in claim 22, furthercomprising: a manually actuated trip mechanism disposed at leastpartially within a housing of said device and configured to breakcontinuity between first and second conductive paths comprisingrespectively corresponding fixed and movable contact stripsindependently of said trip component.